1. Field of the Invention
The invention pertains to a locking apparatus for maintaining the relative angular position of concentric parts.
2. Description of the Prior Art
In various mechanical apparatus and particularly in the assembly and alignment of gyroscopic apparatus, it is necessary to place concentrically rotating parts in a desired angular position relative to each other and then lock the parts in place with an anti-rotation device thereby preventing further relative motion between the parts.
Various techniques have been used in the prior art to lock concentrically rotating parts together in a desired position. General machining operations such as drilling and pinning are not practical in many situations due to problems of maintaining the desired position during drilling and the danger of drilling debris adversely affecting a precision apparatus with close tolerance parts. Another prior art method of locking concentrically rotating parts together uses a jam nut configuration. True jam nuts will counter rotate into one another storing strain energy in deformed threads. In pseudo-jam nut configurations, both nuts rotate in the same direction such that a second nut is run down on top of the first nut. This configuration, although simple, partially unloads the strain energy in the first nuts' threads resulting in the nuts loosening by several degrees thereby permitting undesired movement of several degrees between the two locked parts. The present invention avoids the problems presented by prior art anti-rotation devices. The harmonic locking ring of the present invention restricts relative motion between two concentric parts to a few tenths of a degree.